of the Fishery Board for Scotland. 13 



more. Tlie increase was entirely in round fishes, the quantity of 

 flat-fishes landed having diminished. The reduction in plaice and 

 lemon soles was especially great ; but, on the other hand, witclies 

 and megrims were landed in increased quantities, indicating that 

 the fishing had been carried on on very different grounds in the 

 earlier and later years, and that without information as to the 

 places where the fish were caught, such statistics are of little value 

 in connection with the question of the impoverishment of fishing 

 grounds. 



The second series of Statistics were designed to remedy this 

 defect, the places where the fish were caught being recorded as well 

 as the quantities and the duration of the fishing operations. It is 

 shown that the area of trawling has been greatly extended since 

 1891, and that new grounds, comprising in the North Sea the 

 region lietween the fifty-fathom and the one hundred-fathom line, 

 or about 30,000 square miles, have been opened up by the intro- 

 duction of the otter-trawl. Most of the fish landed by trawlers in 

 the corresponding period in 1901 were obtained from these new 

 grounds, a circumstance which to a large extent accounts for the 

 diminution of the quantity of plaice landed in recent years. Charts 

 and Tables are appended showing the areas in which the fish were^ 

 caught by the trawlers about which particulars were obtained in 

 the first three months of 1891 and 1901, and during the whole of 

 1901. 



The Hatching and Rearing of Food Fishes. 



During the hatching season last year operations were confined 

 to the plaice, of which, as already mentioned, 65,377,000 fertilised 

 eggs were collected, and 51,800,000 plaice fry were obtained. In 

 October the stock of lireeding fishes in the pond numbered 625, 

 and it was found that most of the females had well-developed eggs, 

 showing that their condition in confinement from the previous 

 season had been satisfactory. In December this stock was supple- 

 mented by other 581 fishes, obtained from trawlers, of which a 

 number, as usual, subsequently died. On 8th January, when all 

 the fishes were examined, there were 1071 in the pond, and of the 

 females 560 were considered as likely to spawn normally, the other 

 240 females being uncertain and mostly immature. The first 

 fertilised eggs were collected on 12th January, although spawning 

 did not become general until more than a week later ; it continued 

 to increase for about a month and a half, and was maintained at a 

 high level for other five weeks, most eggs being obtained between 

 the end of the first week and the end of the third week in April. 

 The last eggs were collected on 2nd May. Owing to cold weather 

 with frost and snow in January and February, the temperature of 

 the water was much reduced, and spawning on one or two occasions 

 was interrupted. 



The conditions for the hatching of so large a number of eggs 

 were satisfactory, the salinity of the water falling below 1027 only 

 on fourteen out of 110 days, and the filtration caused little trouble. 



Observations on the Food of Fishes. 



The observations contained in this paper by Mr. T. Scott refer 

 chiefly to the food of small and immature fishes, but the food of 

 several of the larger species is also described. The number of 



